Another great website link with a few idea of how to integrate you Raspberry Pi for uses in the Ham radio world. There are a quite a few good ideas, however using it as a antenna rotator controller was the one that stuck out to me at first glance.
A great ham radio and Raspberry Pi forum website
A great video on the history of transistors, how they work, what they replaced and how they have truly changed the world. We are now reaching the point of prediction where in order to maintain or even continue increases in speed a successor to the transistor must be ‘invented’, quantum mechanics?